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A highly stereoselective Diels-Alder cycloaddition of enones with chiral cyclic 2-amidodienes derived from allenamides.

ABSTRACT: Lewis acid promoted Diels-Alder cycloadditions of a series of de novo chiral cyclic 2-amidodienes are described. These cyclic 2-amidodienes are derived from chiral ?-allyl allenamides via a sequence of E-selective 1,3-H shift and 6?-electron pericyclic ring closure. With enones serving as effective dienophiles, these cycloadditions can be highly diastereoselective depending upon the chiral amide substituent, thereby representing a facile entry to optically enriched [2.2.2]bicyclic manifolds.

SUBMITTER: Fang LC

PROVIDER: S-EPMC3823681 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature

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A highly stereoselective Diels-Alder cycloaddition of enones with chiral cyclic 2-amidodienes derived from allenamides.

Fang Li-Chao LC Hsung Richard P RP Ma Zhi-Xiong ZX Presser William R WR

Organic letters 20130903 18

Lewis acid promoted Diels-Alder cycloadditions of a series of de novo chiral cyclic 2-amidodienes are described. These cyclic 2-amidodienes are derived from chiral α-allyl allenamides via a sequence of E-selective 1,3-H shift and 6π-electron pericyclic ring closure. With enones serving as effective dienophiles, these cycloadditions can be highly diastereoselective depending upon the chiral amide substituent, thereby representing a facile entry to optically enriched [2.2.2]bicyclic manifolds. ...[more]

PMID: 24001055

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